A massive work (Xenakis's longest) for 23 instruments and 4-channel tape, written in 1968 and seldom performed since (it's difficult to stage). This is a new recording, made in 2006, with the original tape material restored, and is in every sense massive: intense, brooding, full of action and wholly self-contained. There is an apparent, but elusive, logic - as with much of Xenakis's music - that comes from his use of stochastic procedures, creating structures that relate to natural phenomena rather than imagination or intelligence. With useful notes (in English and German) and a graphic of the sketch for the score. Also available as a surround sound DVD.